# Relationship history for MSHA mine 4606542

Current hierarchy: **Freeman  Lambert → Contract Coals Inc → No 1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Massey Energy Company → No 1; 1978-03-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Big Bear Mining Company Inc → No 1; 1982-06-01 to 1983-05-19; source msha-controller-operator-history
- **controller_controls_operator:** Massey Energy Company → Big Bear Mining Company Inc; 1982-06-01 to 1983-05-19; source msha-controller-operator-history
- **operator_operates_mine:** Contract Coals Inc → No 1; 1983-05-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Freeman  Lambert → No 1; 1983-05-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Freeman  Lambert → Contract Coals Inc; 1983-05-20 to current/open; source msha-controller-operator-history